An international symposium on Organellar Ion Channels and Transporters will be held in September 1995 at the Marine Biological Laboratory in Woods Hole, Massachusetts, under the auspices of the Society of General Physiologists. The symposium will focus on the biochemistry, molecular biology, structure/function, and physiology of ion channels and transporters found in intracellular membranes such as endoplasmic reticulum, nucleus, and other organelles. The overall aim of the symposium is to integrate the physiological, biochemical, and genetic approaches to the study of this class membrane proteins and provide a focus for discussion of this exciting new frontier of membrane biology. In addition to the keynote address, there will be 24 lectures distributed in five sessions with the following themes: l) Endoplasmic reticulum ion channels and transporters; 2) Mitochondrial channels and transporters; 3) Nuclear channels and transporters; 4) Secretory mechanisms; and 5) Organellar localization of calcium. The speakers will organize their talks to address a mixed audience whose interests will range from protein chemistry to cell physiology. Twenty-four speakers, including-five from abroad, have formally agreed to participate. In addition to the lectures, we will have two poster sessions for contributed papers and one session (New Ideas, New Faces) of shorter talks by young investigators selected from the abstracts submitted for the poster session. Two keynote addresses will be delivered; the first by Dr. Clara Franzini-Armstrong of the University of Pennsylvania who will discuss ryanodine receptor morphology and the second by Dr. Erwin Neher of the Max-Planck-Institute of Gottingen, Germany, who will discuss regulation of intracellular calcium and control of secretion. We have made a special effort to include women speakers; seven of the speakers, including one keynote speaker, are women. The proceedings will be published by the Rockefeller University and has a committed distribution of over 1800 volumes. We expect this publication to constitute a compendium of novel approaches which will influence future research in this field.